TPC 252 Power Supplies Flashcards
Power supplies can receive ______ as an input and deliver ______ as an output.
AC or DC; AC or DC
One possible function of a power conditioner added to a power supply is to ______ the _______
regulate; frequency
An oscillator-driven inverter
Produces a sine wave output.
A voltage regulator changes its _______ in response to changes in the _______.
Resistance; power drawn
Low voltage can be as lethal as high voltage, because the damage is done by the
current passing through your body
The essential parts of an electrochemical cell are the _____ and ______.
electrolyte; electrodes of different metals
Among carbon-zinc cells, the ______ cell works better than the Leclanche cell for continuous use, but not ______.
High Energy; alkaline
A 12V automotive (lead-acid) battery is overcharging if the voltage between the terminals is more than _____.
15V
To protect yourself when working with cells and batteries, you should always be aware that the
battery may produce explosive gases
The best way to provide electricity at remote microwave relay stations is to install _____ cells.
photoelectric
The maximum forward current in most diodes causes a forward voltage drop of ___V.
1
If necessary, you can temporarily connect two diodes in the parallel to provide the necessary _____ in a circuit.
Current; Voltage
A forward-biased SCR _____ current until a trigger pulse passes from the ______ to the cathode.
blocks; gate
The peak-to-peak voltage across the secondary of a transformer is 50V (from -25V to +25V).
0 to +25V, 0 to +12.5V
In a voltage multiplier, the output of the _______ is the input to the _______. Their outputs combine to produce a high output voltage.
Diodes; capacitors
The Power supply to an audio circuit delivers an output that oscillates between +48V and +52V at 60 hz. what is the
2.8
In a power supply, the function of a capacitor is to ______ energy.
store and release
An advantage of an LC filter in a power supply is its _______. A disadvantage is its _______.
low ripple; high cost
A bleeder resistor connected between the terminals of a power supply should have ________ resistance. Its purpose is to __________.
high; discharge the capacitor
The purpose of using external bypass filters in addition to the filters in a power supply is to
prevent interference among circuits on a PCB
A shunt voltage regulator maintains a constat voltage across the load by varying the ______ a path parallel to the load.
current in
In a series regulator, the control circuit must keep the transistor _____ in order to maintain a constat voltage across the load
forward biased
One of the most common types IC voltage regulators has three terminals and is available in the most common preset voltages, ranging from _____ to ______.
5V; 24V
A switching voltage regulator operates by switching rapidly between
full OFF and full ON
In a circuit regulator, _______ triac is the equivalent of ________ SCRs
one; two
In troubleshooting power supplies, you are likely to need an
Oscilloscope
One of the three major steps in troubleshooting power supplies is the _____ test.
section test
As part of the major step in troubleshooting power supplies you should perform an ________ test.
output
When you perform a power-on test on a power supply, you should try to start it at the ______ voltage and then _______
Lowest possible; increase it
If you test a diode with an ohmmeter, you know the diode is good if the resistance is ______ in one direction and ______ in the other direction.
high; low
